/**
 * *
 * ASM: a very small and fast Java bytecode manipulation framework Copyright (c)
 * 2000,2002,2003 INRIA, France Telecom All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * 1. Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer. 2. Redistributions in
 * binary form must reproduce the above copyright notice, this list of
 * conditions and the following disclaimer in the documentation and/or other
 * materials provided with the distribution. 3. Neither the name of the
 * copyright holders nor the names of its contributors may be used to endorse or
 * promote products derived from this software without specific prior written
 * permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */
package org.febit.wit_shaded.asm;

/**
 * A {@link CodeVisitor CodeVisitor} that generates Java bytecode instructions. Each visit method of this class appends
 * the bytecode corresponding to the visited instruction to a byte vector, in the order these methods are called.
 *
 * @author Eric Bruneton
 */
public final class MethodWriter {

    private final ClassWriter cw;
    private final int name;
    private final int desc;
    private final int access;
    private final int[] exceptions;
    /**
     * <tt>true</tt> if the maximum stack size and number of local variables must be automatically computed.
     */
    private static final boolean computeMaxs = true;

    /**
     * Maximum stack size of this method.
     */
    private int maxStack;

    /**
     * Maximum number of local variables for this method.
     */
    private int maxLocals;

    /**
     * The bytecode of this method.
     */
    private final ByteBuffer code;

    /**
     * Number of entries in the catch table of this method.
     */
    private int catchCount;

    /**
     * The catch table of this method.
     */
    private ByteBuffer catchTable;

    /**
     * Number of entries in the LocalVariableTable attribute.
     */
    private int localVarCount;

    /**
     * The LocalVariableTable attribute.
     */
    private ByteBuffer localVar;

//    /**
//     * Indicates if some jump instructions are too small and need to be resized.
//     */
//    private boolean resize;
    /**
     * The (relative) stack size after the last visited instruction. This size is relative to the beginning of the
     * current basic block, i.e., the true stack size after the last visited instruction is equal to the {@link
     * Label#beginStackSize beginStackSize} of the current basic block plus
     * <tt>stackSize</tt>.
     */
    private int stackSize;

    /**
     * The (relative) maximum stack size after the last visited instruction. This size is relative to the beginning of
     * the current basic block, i.e., the true maximum stack size after the last visited instruction is equal to the
     * {@link Label#beginStackSize beginStackSize} of the current basic block plus
     * <tt>stackSize</tt>.
     */
    private int maxStackSize;

    /**
     * The current basic block. This block is the basic block to which the next instruction to be visited must be added.
     */
    private Label currentBlock;

    /**
     * The basic block stack used by the control flow analysis algorithm. This stack is represented by a linked list of
     * {@link Label Label} objects, linked to each other by their {@link Label#next} field. This stack must not be
     * confused with the JVM stack used to execute the JVM instructions!
     */
    private Label blockStack;

    /**
     * The stack size variation corresponding to each JVM instruction. This stack variation is equal to the size of the
     * values produced by an instruction, minus the size of the values consumed by this instruction.
     */
    private static final int[] SIZE;

    // --------------------------------------------------------------------------
    // Fields to optimize the creation of {@link Edge Edge} objects by using a
    // pool of reusable objects. The (shared) pool is a linked list of Edge
    // objects, linked to each other by their {@link Edge#poolNext} field. Each
    // time a MethodWriter needs to allocate an Edge, it removes the first Edge
    // of the pool and adds it to a private list of Edge objects. After the end
    // of the control flow analysis algorithm, the Edge objects in the private
    // list of the MethodWriter are added back to the pool (by appending this
    // private list to the pool list; in order to do this in constant time, both
    // head and tail of the private list are stored in this MethodWriter).
    // --------------------------------------------------------------------------
    /**
     * The head of the list of {@link Edge Edge} objects used by this {@link
     * MethodWriter MethodWriter}. These objects, linked to each other by their {@link Edge#poolNext} field, are added
     * back to the shared pool at the end of the control flow analysis algorithm.
     */
    private Edge head;

    /**
     * The tail of the list of {@link Edge Edge} objects used by this {@link
     * MethodWriter MethodWriter}. These objects, linked to each other by their {@link Edge#poolNext} field, are added
     * back to the shared pool at the end of the control flow analysis algorithm.
     */
    private Edge tail;

    /**
     * The shared pool of {@link Edge Edge} objects. This pool is a linked list of Edge objects, linked to each other by
     * their {@link Edge#poolNext} field.
     */
    private static Edge pool;

    // --------------------------------------------------------------------------
    // Static initializer
    // --------------------------------------------------------------------------
    /**
     * Computes the stack size variation corresponding to each JVM instruction.
     */
    static {
        int i;
        int[] b = new int[202];
        String s
                = "EFFFFFFFFGGFFFGGFFFEEFGFGFEEEEEEEEEEEEEEEEEEEEDEDEDDDDDCDCDEEEEEEEEE"
                + "EEEEEEEEEEEBABABBBBDCFFFGGGEDCDCDCDCDCDCDCDCDCDCEEEEDDDDDDDCDCDCEFEF"
                + "DDEEFFDEDEEEBDDBBDDDDDDCCCCCCCCEFEDDDCDCDEEEEEEEEEEFEEEEEEDDEEDDEE";
        for (i = 0; i < b.length; ++i) {
            b[i] = s.charAt(i) - 'E';
        }
        SIZE = b;

        /* code to generate the above string

         int NA = 0; // not applicable (unused opcode or variable size opcode)

         b = new int[] {
         0,  //NOP,             // visitInsn
         1,  //ACONST_NULL,     // -
         1,  //ICONST_M1,       // -
         1,  //ICONST_0,        // -
         1,  //ICONST_1,        // -
         1,  //ICONST_2,        // -
         1,  //ICONST_3,        // -
         1,  //ICONST_4,        // -
         1,  //ICONST_5,        // -
         2,  //LCONST_0,        // -
         2,  //LCONST_1,        // -
         1,  //FCONST_0,        // -
         1,  //FCONST_1,        // -
         1,  //FCONST_2,        // -
         2,  //DCONST_0,        // -
         2,  //DCONST_1,        // -
         1,  //BIPUSH,          // visitIntInsn
         1,  //SIPUSH,          // -
         1,  //LDC,             // visitLdcInsn
         NA, //LDC_W,           // -
         NA, //LDC2_W,          // -
         1,  //ILOAD,           // visitVarInsn
         2,  //LLOAD,           // -
         1,  //FLOAD,           // -
         2,  //DLOAD,           // -
         1,  //ALOAD,           // -
         NA, //ILOAD_0,         // -
         NA, //ILOAD_1,         // -
         NA, //ILOAD_2,         // -
         NA, //ILOAD_3,         // -
         NA, //LLOAD_0,         // -
         NA, //LLOAD_1,         // -
         NA, //LLOAD_2,         // -
         NA, //LLOAD_3,         // -
         NA, //FLOAD_0,         // -
         NA, //FLOAD_1,         // -
         NA, //FLOAD_2,         // -
         NA, //FLOAD_3,         // -
         NA, //DLOAD_0,         // -
         NA, //DLOAD_1,         // -
         NA, //DLOAD_2,         // -
         NA, //DLOAD_3,         // -
         NA, //ALOAD_0,         // -
         NA, //ALOAD_1,         // -
         NA, //ALOAD_2,         // -
         NA, //ALOAD_3,         // -
         -1, //IALOAD,          // visitInsn
         0,  //LALOAD,          // -
         -1, //FALOAD,          // -
         0,  //DALOAD,          // -
         -1, //AALOAD,          // -
         -1, //BALOAD,          // -
         -1, //CALOAD,          // -
         -1, //SALOAD,          // -
         -1, //ISTORE,          // visitVarInsn
         -2, //LSTORE,          // -
         -1, //FSTORE,          // -
         -2, //DSTORE,          // -
         -1, //ASTORE,          // -
         NA, //ISTORE_0,        // -
         NA, //ISTORE_1,        // -
         NA, //ISTORE_2,        // -
         NA, //ISTORE_3,        // -
         NA, //LSTORE_0,        // -
         NA, //LSTORE_1,        // -
         NA, //LSTORE_2,        // -
         NA, //LSTORE_3,        // -
         NA, //FSTORE_0,        // -
         NA, //FSTORE_1,        // -
         NA, //FSTORE_2,        // -
         NA, //FSTORE_3,        // -
         NA, //DSTORE_0,        // -
         NA, //DSTORE_1,        // -
         NA, //DSTORE_2,        // -
         NA, //DSTORE_3,        // -
         NA, //ASTORE_0,        // -
         NA, //ASTORE_1,        // -
         NA, //ASTORE_2,        // -
         NA, //ASTORE_3,        // -
         -3, //IASTORE,         // visitInsn
         -4, //LASTORE,         // -
         -3, //FASTORE,         // -
         -4, //DASTORE,         // -
         -3, //AASTORE,         // -
         -3, //BASTORE,         // -
         -3, //CASTORE,         // -
         -3, //SASTORE,         // -
         -1, //POP,             // -
         -2, //POP2,            // -
         1,  //DUP,             // -
         1,  //DUP_X1,          // -
         1,  //DUP_X2,          // -
         2,  //DUP2,            // -
         2,  //DUP2_X1,         // -
         2,  //DUP2_X2,         // -
         0,  //SWAP,            // -
         -1, //IADD,            // -
         -2, //LADD,            // -
         -1, //FADD,            // -
         -2, //DADD,            // -
         -1, //ISUB,            // -
         -2, //LSUB,            // -
         -1, //FSUB,            // -
         -2, //DSUB,            // -
         -1, //IMUL,            // -
         -2, //LMUL,            // -
         -1, //FMUL,            // -
         -2, //DMUL,            // -
         -1, //IDIV,            // -
         -2, //LDIV,            // -
         -1, //FDIV,            // -
         -2, //DDIV,            // -
         -1, //IREM,            // -
         -2, //LREM,            // -
         -1, //FREM,            // -
         -2, //DREM,            // -
         0,  //INEG,            // -
         0,  //LNEG,            // -
         0,  //FNEG,            // -
         0,  //DNEG,            // -
         -1, //ISHL,            // -
         -1, //LSHL,            // -
         -1, //ISHR,            // -
         -1, //LSHR,            // -
         -1, //IUSHR,           // -
         -1, //LUSHR,           // -
         -1, //IAND,            // -
         -2, //LAND,            // -
         -1, //IOR,             // -
         -2, //LOR,             // -
         -1, //IXOR,            // -
         -2, //LXOR,            // -
         0,  //IINC,            // visitIincInsn
         1,  //I2L,             // visitInsn
         0,  //I2F,             // -
         1,  //I2D,             // -
         -1, //L2I,             // -
         -1, //L2F,             // -
         0,  //L2D,             // -
         0,  //F2I,             // -
         1,  //F2L,             // -
         1,  //F2D,             // -
         -1, //D2I,             // -
         0,  //D2L,             // -
         -1, //D2F,             // -
         0,  //I2B,             // -
         0,  //I2C,             // -
         0,  //I2S,             // -
         -3, //LCMP,            // -
         -1, //FCMPL,           // -
         -1, //FCMPG,           // -
         -3, //DCMPL,           // -
         -3, //DCMPG,           // -
         -1, //IFEQ,            // visitJumpInsn
         -1, //IFNE,            // -
         -1, //IFLT,            // -
         -1, //IFGE,            // -
         -1, //IFGT,            // -
         -1, //IFLE,            // -
         -2, //IF_ICMPEQ,       // -
         -2, //IF_ICMPNE,       // -
         -2, //IF_ICMPLT,       // -
         -2, //IF_ICMPGE,       // -
         -2, //IF_ICMPGT,       // -
         -2, //IF_ICMPLE,       // -
         -2, //IF_ACMPEQ,       // -
         -2, //IF_ACMPNE,       // -
         0,  //GOTO,            // -
         1,  //JSR,             // -
         0,  //RET,             // visitVarInsn
         -1, //TABLESWITCH,     // visiTableSwitchInsn
         -1, //LOOKUPSWITCH,    // visitLookupSwitch
         -1, //IRETURN,         // visitInsn
         -2, //LRETURN,         // -
         -1, //FRETURN,         // -
         -2, //DRETURN,         // -
         -1, //ARETURN,         // -
         0,  //RETURN,          // -
         NA, //GETSTATIC,       // visitFieldInsn
         NA, //PUTSTATIC,       // -
         NA, //GETFIELD,        // -
         NA, //PUTFIELD,        // -
         NA, //INVOKEVIRTUAL,   // visitMethodInsn
         NA, //INVOKESPECIAL,   // -
         NA, //INVOKESTATIC,    // -
         NA, //INVOKEINTERFACE, // -
         NA, //UNUSED,          // NOT VISITED
         1,  //NEW,             // visitTypeInsn
         0,  //NEWARRAY,        // visitIntInsn
         0,  //ANEWARRAY,       // visitTypeInsn
         0,  //ARRAYLENGTH,     // visitInsn
         NA, //ATHROW,          // -
         0,  //CHECKCAST,       // visitTypeInsn
         0,  //INSTANCEOF,      // -
         -1, //MONITORENTER,    // visitInsn
         -1, //MONITOREXIT,     // -
         NA, //WIDE,            // NOT VISITED
         NA, //MULTIANEWARRAY,  // visitMultiANewArrayInsn
         -1, //IFNULL,          // visitJumpInsn
         -1, //IFNONNULL,       // -
         NA, //GOTO_W,          // -
         NA, //JSR_W,           // -
         };
         for (i = 0; i < b.length; ++i) {
         System.err.print((char)('E' + b[i]));
         }
         System.err.println();
         */
    }

    // --------------------------------------------------------------------------
    // Constructor
    // --------------------------------------------------------------------------
    /**
     * Constructs a CodeWriter.
     *
     * @param cw the class writer in which the method must be added.
     * @param computeMaxs <tt>true</tt> if the maximum stack size and number of local variables must be automatically
     * computed.
     */
    MethodWriter(final ClassWriter cw,
            final int access,
            final String name,
            final String desc,
            final String[] exceptions) {
        this.code = new ByteBuffer();
        this.cw = cw;
        this.access = access;
        this.name = cw.newUTF8(name);
        this.desc = cw.newUTF8(desc);

        if (exceptions != null && exceptions.length > 0) {
            int exceptionCount = exceptions.length;
            this.exceptions = new int[exceptionCount];
            for (int i = 0; i < exceptionCount; ++i) {
                this.exceptions[i] = cw.newClass(exceptions[i]);
            }
        } else {
            this.exceptions = ClassWriter.EMPATY_INTS;
        }

        if (computeMaxs) {
            // pushes the first block onto the stack of blocks to be visited
            blockStack = currentBlock = new Label();
            currentBlock.pushed = true;
            // updates maxLocals
            int size = getArgumentsAndReturnSizes(desc) >> 2;
            if ((access & Constants.ACC_STATIC) != 0) {
                --size;
            }
            if (size > maxLocals) {
                maxLocals = size;
            }
        }
    }

    public void checkCast(String ownerClass) {
        if (!ownerClass.equals("java/lang/Object")) {
            visitTypeInsn(Constants.CHECKCAST, ownerClass);
        }
    }

//    public void pushClass(String name) {
//        visitLdcInsn(cw.newClassItem(name));
//    }
    public void push(int value) {
        if (value > 0 && value <= 5) {
            visitInsn(Constants.ICONST_0 + value);
        } else {
            visitLdcInsn(value);
        }
    }

    public void invokeStatic(
            final String owner,
            final String name,
            final String desc) {
        visitMethodInsn(Constants.INVOKESTATIC, owner, name, desc);
    }

    public void invokeVirtual(
            final String owner,
            final String name,
            final String desc) {
        visitMethodInsn(Constants.INVOKEVIRTUAL, owner, name, desc);
    }

    public void visitMaxs() {
        //public void visitMaxs(final int maxStack, final int maxLocals) {
        if (computeMaxs) {
            // true (non relative) max stack size
            int max = 0;
            // control flow analysis algorithm: while the block stack is not empty,
            // pop a block from this stack, update the max stack size, compute
            // the true (non relative) begin stack size of the successors of this
            // block, and push these successors onto the stack (unless they have
            // already been pushed onto the stack). Note: by hypothesis, the {@link
            // Label#beginStackSize} of the blocks in the block stack are the true
            // (non relative) beginning stack sizes of these blocks.
            Label stack = blockStack;
            while (stack != null) {
                // pops a block from the stack
                Label l = stack;
                stack = stack.next;
                // computes the true (non relative) max stack size of this block
                int start = l.beginStackSize;
                int blockMax = start + l.maxStackSize;
                // updates the global max stack size
                if (blockMax > max) {
                    max = blockMax;
                }
                // analyses the successors of the block
                Edge b = l.successors;
                while (b != null) {
                    l = b.successor;
                    // if this successor has not already been pushed onto the stack...
                    if (!l.pushed) {
                        // computes the true beginning stack size of this successor block
                        l.beginStackSize = start + b.stackSize;
                        // pushes this successor onto the stack
                        l.pushed = true;
                        l.next = stack;
                        stack = l;
                    }
                    b = b.next;
                }
            }
            this.maxStack = max;
            // releases all the Edge objects used by this MethodWriter
            synchronized (SIZE) {
                // appends the [head ... tail] list at the beginning of the pool list
                if (tail != null) {
                    tail.poolNext = pool;
                    pool = head;
                }
            }
        }
//        else {
//            this.maxStack = maxStack;
//            this.maxLocals = maxLocals;
//        }
    }

    public void visitInsn(final int opcode) {
        if (computeMaxs) {
            // updates current and max stack sizes
            int size = stackSize + SIZE[opcode];
            if (size > maxStackSize) {
                maxStackSize = size;
            }
            stackSize = size;
            // if opcode == ATHROW or xRETURN, ends current block (no successor)
            if ((opcode >= Constants.IRETURN && opcode <= Constants.RETURN)
                    || opcode == Constants.ATHROW) {
                if (currentBlock != null) {
                    currentBlock.maxStackSize = maxStackSize;
                    currentBlock = null;
                }
            }
        }
        // adds the instruction to the bytecode of the method
        code.putByte(opcode);
    }

//    public void visitIntInsn(final int opcode, final int operand) {
//        if (computeMaxs && opcode != Constants.NEWARRAY) {
//            // updates current and max stack sizes only if opcode == NEWARRAY
//            // (stack size variation = 0 for BIPUSH or SIPUSH)
//            int size = stackSize + 1;
//            if (size > maxStackSize) {
//                maxStackSize = size;
//            }
//            stackSize = size;
//        }
//        // adds the instruction to the bytecode of the method
//        if (opcode == Constants.SIPUSH) {
//            code.putBS(opcode, operand);
//        } else { // BIPUSH or NEWARRAY
//            code.putBB(opcode, operand);
//        }
//    }
    public void visitVarInsn(final int opcode, final int var) {
        final ByteBuffer code = this.code;
        if (computeMaxs) {
            // updates current and max stack sizes
            if (opcode == Constants.RET) {
                // no stack change, but end of current block (no successor)
                if (currentBlock != null) {
                    currentBlock.maxStackSize = maxStackSize;
                    currentBlock = null;
                }
            } else { // xLOAD or xSTORE
                int size = stackSize + SIZE[opcode];
                if (size > maxStackSize) {
                    maxStackSize = size;
                }
                stackSize = size;
            }
            // updates max locals
            int n;
//            if (opcode == Constants.LLOAD || opcode == Constants.DLOAD
//                    || opcode == Constants.LSTORE || opcode == Constants.DSTORE) {
//                n = var + 2;
//            } else {
            n = var + 1;
//            }
            if (n > maxLocals) {
                maxLocals = n;
            }
        }
        // adds the instruction to the bytecode of the method
        if (var < 4 && opcode != Constants.RET) {
            int opt;
            if (opcode < Constants.ISTORE) {
                opt = 26 /*ILOAD_0*/ + ((opcode - Constants.ILOAD) << 2) + var;
            } else {
                opt = 59 /*ISTORE_0*/ + ((opcode - Constants.ISTORE) << 2) + var;
            }
            code.putByte(opt);
        } else if (var >= 256) {
            code.putByte(196 /*WIDE*/).putBS(opcode, var);
        } else {
            code.putBB(opcode, var);
        }
    }

    public void visitTypeInsn(final int opcode, final String desc) {
        if (computeMaxs && opcode == Constants.NEW) {
            // updates current and max stack sizes only if opcode == NEW
            // (stack size variation = 0 for ANEWARRAY, CHECKCAST, INSTANCEOF)
            int size = stackSize + 1;
            if (size > maxStackSize) {
                maxStackSize = size;
            }
            stackSize = size;
        }
        // adds the instruction to the bytecode of the method
        code.putBS(opcode, cw.newClass(desc));
    }

    public void visitFieldInsn(
            final int opcode,
            final String owner,
            final String name,
            final String desc) {
        if (computeMaxs) {
            int size;
            // computes the stack size variation
            char c = desc.charAt(0);
            switch (opcode) {
                case Constants.GETSTATIC:
                    size = stackSize + (c == 'D' || c == 'J' ? 2 : 1);
                    break;
//                case Constants.PUTSTATIC:
//                    size = stackSize + (c == 'D' || c == 'J' ? -2 : -1);
//                    break;
                case Constants.GETFIELD:
                    size = stackSize + (c == 'D' || c == 'J' ? 1 : 0);
                    break;
                //case Constants.PUTFIELD:
                default:
                    size = stackSize + (c == 'D' || c == 'J' ? -3 : -2);
                    break;
            }
            // updates current and max stack sizes
            if (size > maxStackSize) {
                maxStackSize = size;
            }
            stackSize = size;
        }
        // adds the instruction to the bytecode of the method
        code.putBS(opcode, cw.newField(owner, name, desc));
    }

    public void visitMethodInsn(
            final int opcode,
            final String owner,
            final String name,
            final String desc) {
        boolean itf = opcode == Constants.INVOKEINTERFACE;
        Item i = cw.newMethodItem(owner, name, desc, itf);
        int argSize = i.argSize;
        if (computeMaxs) {
            // computes the stack size variation. In order not to recompute several
            // times this variation for the same Item, we use the intVal field of
            // this item to store this variation, once it has been computed. More
            // precisely this intVal field stores the sizes of the arguments and of
            // the return value corresponding to desc.
            if (argSize == 0) {
                // the above sizes have not been computed yet, so we compute them...
                i.argSize = argSize = getArgumentsAndReturnSizes(desc);
            }
            int size = stackSize - (argSize >> 2) + (argSize & 0x03);
            if (opcode == Constants.INVOKESTATIC) {
                size += 1;
            }
            // updates current and max stack sizes
            if (size > maxStackSize) {
                maxStackSize = size;
            }
            stackSize = size;
        }
        // adds the instruction to the bytecode of the method
        final ByteBuffer code = this.code;
        if (itf) {
            if (!computeMaxs) {
                if (argSize == 0) {
                    argSize = getArgumentsAndReturnSizes(desc);
                    i.argSize = argSize;
                }
            }
            code.putBS(Constants.INVOKEINTERFACE, i.index).putBB(argSize >> 2, 0);
        } else {
            code.putBS(opcode, i.index);
        }
    }

    public void visitJumpInsn(final int opcode, final Label label) {
        final ByteBuffer code = this.code;
        if (computeMaxs) {
            if (opcode == Constants.GOTO) {
                // no stack change, but end of current block (with one new successor)
                if (currentBlock != null) {
                    currentBlock.maxStackSize = maxStackSize;
                    addSuccessor(stackSize, label);
                    currentBlock = null;
                }
            } else if (opcode == Constants.JSR) {
                if (currentBlock != null) {
                    addSuccessor(stackSize + 1, label);
                }
            } else {
                // updates current stack size (max stack size unchanged because stack
                // size variation always negative in this case)
                stackSize += SIZE[opcode];
                if (currentBlock != null) {
                    addSuccessor(stackSize, label);
                }
            }
        }
        // adds the instruction to the bytecode of the method
        if (label.resolved && label.position - code.length < Short.MIN_VALUE) {
            // case of a backward jump with an offset < -32768. In this case we
            // automatically replace GOTO with GOTO_W, JSR with JSR_W and IFxxx <l>
            // with IFNOTxxx <l'> GOTO_W <l>, where IFNOTxxx is the "opposite" opcode
            // of IFxxx (i.e., IFNE for IFEQ) and where <l'> designates the
            // instruction just after the GOTO_W.
            if (opcode == Constants.GOTO) {
                code.putByte(200); // GOTO_W
            } else if (opcode == Constants.JSR) {
                code.putByte(201); // JSR_W
            } else {
                code.putByte(opcode <= 166 ? ((opcode + 1) ^ 1) - 1 : opcode ^ 1)
                        .putShort(8) // jump offset
                        .putByte(200); // GOTO_W
            }
            label.put(this, code, code.length - 1, true);
        } else {
            // case of a backward jump with an offset >= -32768, or of a forward jump
            // with, of course, an unknown offset. In these cases we store the offset
            // in 2 bytes (which will be increased in resizeInstructions, if needed).
            code.putByte(opcode);
            label.put(this, code, code.length - 1, false);
        }
    }

    public void visitLabel(final Label label) {
        if (computeMaxs) {
            if (currentBlock != null) {
                // ends current block (with one new successor)
                currentBlock.maxStackSize = maxStackSize;
                addSuccessor(stackSize, label);
            }
            // begins a new current block,
            // resets the relative current and max stack sizes
            currentBlock = label;
            stackSize = 0;
            maxStackSize = 0;
        }


        // resolves previous forward references to label, if any
        /* resize |= */ label.resolve(this, code.length, code.data);
    }

    public void visitLdcInsn(final Object cst) {
        Item i = cw.newConstItem(cst);
        if (computeMaxs) {
            int size;
            // computes the stack size variation
            size = stackSize = stackSize + ((i.type == ClassWriter.LONG || i.type == ClassWriter.DOUBLE) ? 2 : 1);
            // updates current and max stack sizes
            if (size > maxStackSize) {
                maxStackSize = size;
            }
        }
        // adds the instruction to the bytecode of the method
        final ByteBuffer code = this.code;
        int index = i.index;
        if (i.type == ClassWriter.LONG || i.type == ClassWriter.DOUBLE) {
            code.putBS(20 /*LDC2_W*/, index);
        } else if (index >= 256) {
            code.putBS(19 /*LDC_W*/, index);
        } else {
            code.putBB(Constants.LDC, index);
        }
    }

//    public void visitIincInsn(final int var, final int increment) {
//        if (computeMaxs) {
//            // updates max locals only (no stack change)
//            int n = var + 1;
//            if (n > maxLocals) {
//                maxLocals = n;
//            }
//        }
//        // adds the instruction to the bytecode of the method
//        if ((var > 255) || (increment > 127) || (increment < -128)) {
//            code.putByte(196 /*WIDE*/).putBS(Constants.IINC, var).putShort(increment);
//        } else {
//            code.putByte(Constants.IINC).putBB(var, increment);
//        }
//    }
//    public void visitTableSwitchInsn(
//            final int min,
//            final int max,
//            final Label dflt,
//            final Label labels[]) {
//        if (computeMaxs) {
//            // updates current stack size (max stack size unchanged)
//            --stackSize;
//            // ends current block (with many new successors)
//            if (currentBlock != null) {
//                currentBlock.maxStackSize = maxStackSize;
//                addSuccessor(stackSize, dflt);
//                for (int i = 0; i < labels.length; ++i) {
//                    addSuccessor(stackSize, labels[i]);
//                }
//                currentBlock = null;
//            }
//        }
//        // adds the instruction to the bytecode of the method
//        int source = code.length;
//        code.putByte(Constants.TABLESWITCH);
//        while (code.length % 4 != 0) {
//            code.putByte(0);
//        }
//        dflt.put(this, code, source, true);
//        code.putInt(min).putInt(max);
//        for (int i = 0; i < labels.length; ++i) {
//            labels[i].put(this, code, source, true);
//        }
//    }
    public void visitLookupSwitchInsn(
            final Label dflt,
            final int keys[],
            final Label labels[]) {
        if (computeMaxs) {
            // updates current stack size (max stack size unchanged)
            --stackSize;
            // ends current block (with many new successors)
            if (currentBlock != null) {
                currentBlock.maxStackSize = maxStackSize;
                addSuccessor(stackSize, dflt);
                for (int i = 0; i < labels.length; ++i) {
                    addSuccessor(stackSize, labels[i]);
                }
                currentBlock = null;
            }
        }
        final ByteBuffer code = this.code;
        // adds the instruction to the bytecode of the method
        int source = code.length;
        code.putByte(Constants.LOOKUPSWITCH);
        while (code.length % 4 != 0) {
            code.putByte(0);
        }
        dflt.put(this, code, source, true);
        code.putInt(labels.length);
        for (int i = 0; i < labels.length; ++i) {
            code.putInt(keys[i]);
            labels[i].put(this, code, source, true);
        }
    }

//    public void visitMultiANewArrayInsn(final String desc, final int dims) {
//        if (computeMaxs) {
//            // updates current stack size (max stack size unchanged because stack
//            // size variation always negative or null)
//            stackSize += 1 - dims;
//        }
//        // adds the instruction to the bytecode of the method
//        code.putBS(Constants.MULTIANEWARRAY, cw.newClass(desc)).putByte(dims);
//    }
//    public void visitTryCatchBlock(
//            final Label start,
//            final Label end,
//            final Label handler,
//            final String type) {
//        if (computeMaxs) {
//            // pushes handler block onto the stack of blocks to be visited
//            if (!handler.pushed) {
//                handler.beginStackSize = 1;
//                handler.pushed = true;
//                handler.next = blockStack;
//                blockStack = handler;
//            }
//        }
//        ++catchCount;
//        if (catchTable == null) {
//            catchTable = new ByteBuffer();
//        }
//        catchTable.putShort(start.position)
//                .putShort(end.position)
//                .putShort(handler.position)
//                .putShort(type != null ? cw.newClass(type) : 0);
//    }
//    public void visitLocalVariable(
//            final String name,
//            final String desc,
//            final Label start,
//            final Label end,
//            final int index) {
//        if (localVar == null) {
//            cw.newUTF8("LocalVariableTable");
//            localVar = new ByteBuffer();
//        }
//        ++localVarCount;
//        localVar.putShort(start.position)
//                .putShort(end.position - start.position)
//                .putShort(cw.newUTF8(name))
//                .putShort(cw.newUTF8(desc))
//                .putShort(index);
//    }
    // --------------------------------------------------------------------------
    // Utility methods: control flow analysis algorithm
    // --------------------------------------------------------------------------
    /**
     * Computes the size of the arguments and of the return value of a method.
     *
     * @param desc the descriptor of a method.
     * @return the size of the arguments of the method (plus one for the implicit this argument), argSize, and the size
     * of its return value, retSize, packed into a single int i = <tt>(argSize << 2) | retSize</tt> (argSize is
     * therefore equal to <tt>i >> 2</tt>, and retSize to
     * <tt>i & 0x03</tt>).
     */
    private static int getArgumentsAndReturnSizes(final String desc) {
        int n = 1;
        int c = 1;
        for (;;) {
            char car = desc.charAt(c++);
            if (car == ')') {
                car = desc.charAt(c);
                return n << 2 | (car == 'V' ? 0 : (car == 'D' || car == 'J' ? 2 : 1));
            } else if (car == 'L') {
                while (desc.charAt(c++) != ';') {
                }
                n += 1;
            } else if (car == '[') {
                while ((car = desc.charAt(c)) == '[') {
                    ++c;
                }
                if (car == 'D' || car == 'J') {
                    n -= 1;
                }
            } else if (car == 'D' || car == 'J') {
                n += 2;
            } else {
                n += 1;
            }
        }
    }

    /**
     * Adds a successor to the {@link #currentBlock currentBlock} block.
     *
     * @param stackSize the current (relative) stack size in the current block.
     * @param successor the successor block to be added to the current block.
     */
    private void addSuccessor(final int stackSize, final Label successor) {
        Edge b;
        // creates a new Edge object or reuses one from the shared pool
        synchronized (SIZE) {
            if (pool == null) {
                b = new Edge();
            } else {
                b = pool;
                // removes b from the pool
                pool = pool.poolNext;
            }
        }
        // adds the previous Edge to the list of Edges used by this MethodWriter
        if (tail == null) {
            tail = b;
        }
        b.poolNext = head;
        head = b;
        // initializes the previous Edge object...
        b.stackSize = stackSize;
        b.successor = successor;
        // ...and adds it to the successor list of the currentBlock block
        b.next = currentBlock.successors;
        currentBlock.successors = b;
    }

    // --------------------------------------------------------------------------
    // Utility methods: dump bytecode array
    // --------------------------------------------------------------------------
    /**
     * Returns the size of the bytecode of this method.
     *
     * @return the size of the bytecode of this method.
     */
    final int getSize() {
//        if (resize) {
//            // replaces the temporary jump opcodes introduced by Label.resolve.
//            resizeInstructions(ClassWriter.EMPATY_INTS, ClassWriter.EMPATY_INTS, 0);
//        }
        int size = 8;
        if (code.length > 0) {
            cw.newUTF8("Code");
            size += 18 + code.length + 8 * catchCount;
            if (localVar != null) {
                size += 8 + localVar.length;
            }
        }
        int exceptionCount = exceptions.length;
        if (exceptionCount > 0) {
            cw.newUTF8("Exceptions");
            size += 8 + 2 * exceptionCount;
        }
//        if ((access & Constants.ACC_SYNTHETIC) != 0) {
//            cw.newUTF8("Synthetic");
//            size += 6;
//        }
//        if ((access & Constants.ACC_DEPRECATED) != 0) {
//            cw.newUTF8("Deprecated");
//            size += 6;
//        }
        return size;
    }

    /**
     * Puts the bytecode of this method in the given byte vector.
     *
     * @param out the byte vector into which the bytecode of this method must be copied.
     */
    final void renderTo(final ByteBuffer out) {
        final ByteBuffer code = this.code;
        out.putShort(access).putShort(name).putShort(desc);
        int attributeCount = 0;
        if (code.length > 0) {
            ++attributeCount;
        }
        int exceptionCount = exceptions.length;
        if (exceptionCount > 0) {
            ++attributeCount;
        }
//        if ((access & Constants.ACC_SYNTHETIC) != 0) {
//            ++attributeCount;
//        }
//        if ((access & Constants.ACC_DEPRECATED) != 0) {
//            ++attributeCount;
//        }
        out.putShort(attributeCount);
        if (code.length > 0) {
            int size = 12 + code.length + 8 * catchCount;
            if (localVar != null) {
                size += 8 + localVar.length;
            }
            out.putShort(cw.newUTF8("Code")).putInt(size)
                    .putShort(maxStack).putShort(maxLocals)
                    .putInt(code.length).put(code)
                    .putShort(catchCount);
            if (catchCount > 0) {
                out.put(catchTable);
            }
            attributeCount = 0;
            if (localVar != null) {
                ++attributeCount;
            }
            out.putShort(attributeCount);
            if (localVar != null) {
                out.putShort(cw.newUTF8("LocalVariableTable"))
                        .putInt(localVar.length + 2).putShort(localVarCount)
                        .put(localVar);
            }
        }
        if (exceptionCount > 0) {
            out.putShort(cw.newUTF8("Exceptions")).putInt(2 * exceptionCount + 2)
                    .putShort(exceptionCount);
            for (int i = 0; i < exceptionCount; ++i) {
                out.putShort(exceptions[i]);
            }
        }
//        if ((access & Constants.ACC_SYNTHETIC) != 0) {
//            out.putShort(cw.newUTF8("Synthetic")).putInt(0);
//        }
//        if ((access & Constants.ACC_DEPRECATED) != 0) {
//            out.putShort(cw.newUTF8("Deprecated")).putInt(0);
//        }
    }

//    // --------------------------------------------------------------------------
//    // Utility methods: instruction resizing (used to handle GOTO_W and JSR_W)
//    // --------------------------------------------------------------------------
//    /**
//     * Resizes the designated instructions, while keeping jump offsets and
//     * instruction addresses consistent. This may require to resize other
//     * existing instructions, or even to introduce new instructions: for
//     * example, increasing the size of an instruction by 2 at the middle of a
//     * method can increases the offset of an IFEQ instruction from 32766 to
//     * 32768, in which case IFEQ 32766 must be replaced with IFNEQ 8 GOTO_W
//     * 32765. This, in turn, may require to increase the size of another jump
//     * instruction, and so on... All these operations are handled automatically
//     * by this method.
//     * <p>
//     * <i>This method must be called after all the method that is being built
//     * has been visited</i>. In particular, the {@link Label Label} objects used
//     * to construct the method are no longer valid after this method has been
//     * called.
//     *
//     * @param indexes current positions of the instructions to be resized. Each
//     * instruction must be designated by the index of its <i>last</i> byte, plus
//     * one (or, in other words, by the index of the <i>first</i> byte of the
//     * <i>next</i> instruction).
//     * @param sizes the number of bytes to be <i>added</i> to the above
//     * instructions. More precisely, for each i &lt; <tt>len</tt>,
//     * <tt>sizes</tt>[i] bytes will be added at the end of the instruction
//     * designated by <tt>indexes</tt>[i] or, if <tt>sizes</tt>[i] is negative,
//     * the <i>last</i> |<tt>sizes[i]</tt>| bytes of the instruction will be
//     * removed (the instruction size <i>must not</i> become negative or null).
//     * The gaps introduced by this method must be filled in "manually" in the
//     * array returned by the {@link #getCode getCode} method.
//     * @param len the number of instruction to be resized. Must be smaller than
//     * or equal to <tt>indexes</tt>.length and <tt>sizes</tt>.length.
//     * @return the <tt>indexes</tt> array, which now contains the new positions
//     * of the resized instructions (designated as above).
//     */
//    protected int[] resizeInstructions(
//            final int[] indexes,
//            final int[] sizes,
//            final int len) {
//        byte[] b = code.data; // bytecode of the method
//        int u, v, label;      // indexes in b
//        int i, j;             // loop indexes
//
//        // 1st step:
//        // As explained above, resizing an instruction may require to resize another
//        // one, which may require to resize yet another one, and so on. The first
//        // step of the algorithm consists in finding all the instructions that
//        // need to be resized, without modifying the code. This is done by the
//        // following "fix point" algorithm:
//        // - parse the code to find the jump instructions whose offset will need
//        //   more than 2 bytes to be stored (the future offset is computed from the
//        //   current offset and from the number of bytes that will be inserted or
//        //   removed between the source and target instructions). For each such
//        //   instruction, adds an entry in (a copy of) the indexes and sizes arrays
//        //   (if this has not already been done in a previous iteration!)
//        // - if at least one entry has been added during the previous step, go back
//        //   to the beginning, otherwise stop.
//        // In fact the real algorithm is complicated by the fact that the size of
//        // TABLESWITCH and LOOKUPSWITCH instructions depends on their position in
//        // the bytecode (because of padding). In order to ensure the convergence of
//        // the algorithm, the number of bytes to be added or removed from these
//        // instructions is over estimated during the previous loop, and computed
//        // exactly only after the loop is finished (this requires another pass to
//        // parse the bytecode of the method).
//        int[] allIndexes = new int[len]; // copy of indexes
//        int[] allSizes = new int[len];   // copy of sizes
//        boolean[] resize;                // instructions to be resized
//        int newOffset;                   // future offset of a jump instruction
//
//        System.arraycopy(indexes, 0, allIndexes, 0, len);
//        System.arraycopy(sizes, 0, allSizes, 0, len);
//        resize = new boolean[code.length];
//
//        int state = 3; // 3 = loop again, 2 = loop ended, 1 = last pass, 0 = done
//        do {
//            if (state == 3) {
//                state = 2;
//            }
//            u = 0;
//            while (u < b.length) {
//                int opcode = b[u] & 0xFF;  // opcode of current instruction
//                int insert = 0;            // bytes to be added after this instruction
//
//                switch (ClassWriter.TYPE[opcode]) {
//                    case ClassWriter.NOARG_INSN:
//                    case ClassWriter.IMPLVAR_INSN:
//                        u += 1;
//                        break;
//                    case ClassWriter.LABEL_INSN:
//                        if (opcode > 201) {
//                            // converts temporary opcodes 202 to 217 (inclusive), 218 and 219
//                            // to IFEQ ... JSR (inclusive), IFNULL and IFNONNULL
//                            opcode = opcode < 218 ? opcode - 49 : opcode - 20;
//                            label = u + readUnsignedShort(b, u + 1);
//                        } else {
//                            label = u + readShort(b, u + 1);
//                        }
//                        newOffset = getNewOffset(allIndexes, allSizes, u, label);
//                        if (newOffset < Short.MIN_VALUE || newOffset > Short.MAX_VALUE) {
//                            if (!resize[u]) {
//                                if (opcode == Constants.GOTO || opcode == Constants.JSR) {
//                                    // two additional bytes will be required to replace this
//                                    // GOTO or JSR instruction with a GOTO_W or a JSR_W
//                                    insert = 2;
//                                } else {
//                                    // five additional bytes will be required to replace this
//                                    // IFxxx <l> instruction with IFNOTxxx <l'> GOTO_W <l>, where
//                                    // IFNOTxxx is the "opposite" opcode of IFxxx (i.e., IFNE for
//                                    // IFEQ) and where <l'> designates the instruction just after
//                                    // the GOTO_W.
//                                    insert = 5;
//                                }
//                                resize[u] = true;
//                            }
//                        }
//                        u += 3;
//                        break;
//                    case ClassWriter.LABELW_INSN:
//                        u += 5;
//                        break;
////                    case ClassWriter.TABL_INSN:
////                        if (state == 1) {
////                            // true number of bytes to be added (or removed) from this
////                            // instruction = (future number of padding bytes - current number
////                            // of padding byte) - previously over estimated variation =
////                            // = ((3 - newOffset%4) - (3 - u%4)) - u%4
////                            // = (-newOffset%4 + u%4) - u%4
////                            // = -(newOffset & 3)
////                            newOffset = getNewOffset(allIndexes, allSizes, 0, u);
////                            insert = -(newOffset & 3);
////                        } else if (!resize[u]) {
////                            // over estimation of the number of bytes to be added to this
////                            // instruction = 3 - current number of padding bytes = 3 - (3 -
////                            // u%4) = u%4 = u & 3
////                            insert = u & 3;
////                            resize[u] = true;
////                        }
////                        // skips instruction
////                        u = u + 4 - (u & 3);
////                        u += 4 * (readInt(b, u + 8) - readInt(b, u + 4) + 1) + 12;
////                        break;
//                    case ClassWriter.LOOK_INSN:
//                        if (state == 1) {
//                            // like TABL_INSN
//                            newOffset = getNewOffset(allIndexes, allSizes, 0, u);
//                            insert = -(newOffset & 3);
//                        } else if (!resize[u]) {
//                            // like TABL_INSN
//                            insert = u & 3;
//                            resize[u] = true;
//                        }
//                        // skips instruction
//                        u = u + 4 - (u & 3);
//                        u += 8 * readInt(b, u + 4) + 8;
//                        break;
//                    case ClassWriter.WIDE_INSN:
//                        opcode = b[u + 1] & 0xFF;
//                        if (opcode == Constants.IINC) {
//                            u += 6;
//                        } else {
//                            u += 4;
//                        }
//                        break;
//                    case ClassWriter.VAR_INSN:
//                    case ClassWriter.SBYTE_INSN:
//                    case ClassWriter.LDC_INSN:
//                        u += 2;
//                        break;
//                    case ClassWriter.SHORT_INSN:
//                    case ClassWriter.LDCW_INSN:
//                    case ClassWriter.FIELDORMETH_INSN:
//                    case ClassWriter.TYPE_INSN:
//                    case ClassWriter.IINC_INSN:
//                        u += 3;
//                        break;
//                    case ClassWriter.ITFMETH_INSN:
//                        u += 5;
//                        break;
//                    // case ClassWriter.MANA_INSN:
//                    default:
//                        u += 4;
//                        break;
//                }
//                if (insert != 0) {
//                    // adds a new (u, insert) entry in the allIndexes and allSizes arrays
//                    int[] newIndexes = new int[allIndexes.length + 1];
//                    int[] newSizes = new int[allSizes.length + 1];
//                    System.arraycopy(allIndexes, 0, newIndexes, 0, allIndexes.length);
//                    System.arraycopy(allSizes, 0, newSizes, 0, allSizes.length);
//                    newIndexes[allIndexes.length] = u;
//                    newSizes[allSizes.length] = insert;
//                    allIndexes = newIndexes;
//                    allSizes = newSizes;
//                    if (insert > 0) {
//                        state = 3;
//                    }
//                }
//            }
//            if (state < 3) {
//                --state;
//            }
//        } while (state != 0);
//
//        // 2nd step:
//        // copies the bytecode of the method into a new bytevector, updates the
//        // offsets, and inserts (or removes) bytes as requested.
//        ByteBuffer newCode = new ByteBuffer(code.length);
//
//        u = 0;
//        while (u < code.length) {
//            for (i = allIndexes.length - 1; i >= 0; --i) {
//                if (allIndexes[i] == u) {
//                    if (i < len) {
//                        if (sizes[i] > 0) {
//                            newCode.put(null, 0, sizes[i]);
//                        } else {
//                            newCode.length += sizes[i];
//                        }
//                        indexes[i] = newCode.length;
//                    }
//                }
//            }
//            int opcode = b[u] & 0xFF;
//            switch (ClassWriter.TYPE[opcode]) {
//                case ClassWriter.NOARG_INSN:
//                case ClassWriter.IMPLVAR_INSN:
//                    newCode.putByte(opcode);
//                    u += 1;
//                    break;
//                case ClassWriter.LABEL_INSN:
//                    if (opcode > 201) {
//                        // changes temporary opcodes 202 to 217 (inclusive), 218 and 219
//                        // to IFEQ ... JSR (inclusive), IFNULL and IFNONNULL
//                        opcode = opcode < 218 ? opcode - 49 : opcode - 20;
//                        label = u + readUnsignedShort(b, u + 1);
//                    } else {
//                        label = u + readShort(b, u + 1);
//                    }
//                    newOffset = getNewOffset(allIndexes, allSizes, u, label);
//                    if (resize[u]) {
//                        // replaces GOTO with GOTO_W, JSR with JSR_W and IFxxx <l> with
//                        // IFNOTxxx <l'> GOTO_W <l>, where IFNOTxxx is the "opposite" opcode
//                        // of IFxxx (i.e., IFNE for IFEQ) and where <l'> designates the
//                        // instruction just after the GOTO_W.
//                        if (opcode == Constants.GOTO) {
//                            newCode.putByte(200); // GOTO_W
//                        } else if (opcode == Constants.JSR) {
//                            newCode.putByte(201); // JSR_W
//                        } else {
//                            newCode.putByte(opcode <= 166 ? ((opcode + 1) ^ 1) - 1 : opcode ^ 1)
//                                    .putShort(8) // jump offset
//                                    .putByte(200); // GOTO_W
//                            newOffset -= 3;    // newOffset now computed from start of GOTO_W
//                        }
//                        newCode.putInt(newOffset);
//                    } else {
//                        newCode.putByte(opcode);
//                        newCode.putShort(newOffset);
//                    }
//                    u += 3;
//                    break;
//                case ClassWriter.LABELW_INSN:
//                    label = u + readInt(b, u + 1);
//                    newOffset = getNewOffset(allIndexes, allSizes, u, label);
//                    newCode.putByte(opcode);
//                    newCode.putInt(newOffset);
//                    u += 5;
//                    break;
////                case ClassWriter.TABL_INSN:
////                    // skips 0 to 3 padding bytes
////                    v = u;
////                    u = u + 4 - (v & 3);
////                    // reads and copies instruction
////                    newCode.putByte(Constants.TABLESWITCH);
////                    while (newCode.length % 4 != 0) {
////                        newCode.putByte(0);
////                    }
////                    label = v + readInt(b, u);
////                    u += 4;
////                    newOffset = getNewOffset(allIndexes, allSizes, v, label);
////                    newCode.putInt(newOffset);
////                    j = readInt(b, u);
////                    u += 4;
////                    newCode.putInt(j);
////                    j = readInt(b, u) - j + 1;
////                    u += 4;
////                    newCode.putInt(readInt(b, u - 4));
////                    for (; j > 0; --j) {
////                        label = v + readInt(b, u);
////                        u += 4;
////                        newOffset = getNewOffset(allIndexes, allSizes, v, label);
////                        newCode.putInt(newOffset);
////                    }
////                    break;
//                case ClassWriter.LOOK_INSN:
//                    // skips 0 to 3 padding bytes
//                    v = u;
//                    u = u + 4 - (v & 3);
//                    // reads and copies instruction
//                    newCode.putByte(Constants.LOOKUPSWITCH);
//                    while (newCode.length % 4 != 0) {
//                        newCode.putByte(0);
//                    }
//                    label = v + readInt(b, u);
//                    u += 4;
//                    newOffset = getNewOffset(allIndexes, allSizes, v, label);
//                    newCode.putInt(newOffset);
//                    j = readInt(b, u);
//                    u += 4;
//                    newCode.putInt(j);
//                    for (; j > 0; --j) {
//                        newCode.putInt(readInt(b, u));
//                        u += 4;
//                        label = v + readInt(b, u);
//                        u += 4;
//                        newOffset = getNewOffset(allIndexes, allSizes, v, label);
//                        newCode.putInt(newOffset);
//                    }
//                    break;
//                case ClassWriter.WIDE_INSN:
//                    opcode = b[u + 1] & 0xFF;
//                    if (opcode == Constants.IINC) {
//                        newCode.put(b, u, 6);
//                        u += 6;
//                    } else {
//                        newCode.put(b, u, 4);
//                        u += 4;
//                    }
//                    break;
//                case ClassWriter.VAR_INSN:
//                case ClassWriter.SBYTE_INSN:
//                case ClassWriter.LDC_INSN:
//                    newCode.put(b, u, 2);
//                    u += 2;
//                    break;
//                case ClassWriter.SHORT_INSN:
//                case ClassWriter.LDCW_INSN:
//                case ClassWriter.FIELDORMETH_INSN:
//                case ClassWriter.TYPE_INSN:
//                case ClassWriter.IINC_INSN:
//                    newCode.put(b, u, 3);
//                    u += 3;
//                    break;
//                case ClassWriter.ITFMETH_INSN:
//                    newCode.put(b, u, 5);
//                    u += 5;
//                    break;
//                // case MANA_INSN:
//                default:
//                    newCode.put(b, u, 4);
//                    u += 4;
//                    break;
//            }
//        }
//
//        // updates the instructions addresses in the
//        // catch, local var and line number tables
//        if (catchTable != null) {
//            b = catchTable.data;
//            u = 0;
//            while (u < catchTable.length) {
//                writeShort(b, u, getNewOffset(
//                        allIndexes, allSizes, 0, readUnsignedShort(b, u)));
//                writeShort(b, u + 2, getNewOffset(
//                        allIndexes, allSizes, 0, readUnsignedShort(b, u + 2)));
//                writeShort(b, u + 4, getNewOffset(
//                        allIndexes, allSizes, 0, readUnsignedShort(b, u + 4)));
//                u += 8;
//            }
//        }
//        if (localVar != null) {
//            b = localVar.data;
//            u = 0;
//            while (u < localVar.length) {
//                label = readUnsignedShort(b, u);
//                newOffset = getNewOffset(allIndexes, allSizes, 0, label);
//                writeShort(b, u, newOffset);
//                label += readUnsignedShort(b, u + 2);
//                newOffset = getNewOffset(allIndexes, allSizes, 0, label) - newOffset;
//                writeShort(b, u + 2, newOffset);
//                u += 10;
//            }
//        }
//
//        // replaces old bytecodes with new ones
//        code = newCode;
//
//        // returns the positions of the resized instructions
//        return indexes;
//    }
//
//    /**
//     * Reads an unsigned short value in the given byte array.
//     *
//     * @param b a byte array.
//     * @param index the start index of the value to be read.
//     * @return the read value.
//     */
//    static int readUnsignedShort(final byte[] b, final int index) {
//        return ((b[index] & 0xFF) << 8) | (b[index + 1] & 0xFF);
//    }
//
//    /**
//     * Reads a signed short value in the given byte array.
//     *
//     * @param b a byte array.
//     * @param index the start index of the value to be read.
//     * @return the read value.
//     */
//    static short readShort(final byte[] b, final int index) {
//        return (short) (((b[index] & 0xFF) << 8) | (b[index + 1] & 0xFF));
//    }
//
//    /**
//     * Reads a signed int value in the given byte array.
//     *
//     * @param b a byte array.
//     * @param index the start index of the value to be read.
//     * @return the read value.
//     */
//    static int readInt(final byte[] b, final int index) {
//        return ((b[index] & 0xFF) << 24)
//                | ((b[index + 1] & 0xFF) << 16)
//                | ((b[index + 2] & 0xFF) << 8)
//                | (b[index + 3] & 0xFF);
//    }
//
//    /**
//     * Writes a short value in the given byte array.
//     *
//     * @param b a byte array.
//     * @param index where the first byte of the short value must be written.
//     * @param s the value to be written in the given byte array.
//     */
//    static void writeShort(final byte[] b, final int index, final int s) {
//        b[index] = (byte) (s >>> 8);
//        b[index + 1] = (byte) s;
//    }
//
//    /**
//     * Computes the future value of a bytecode offset.
//     * <p>
//     * Note: it is possible to have several entries for the same instruction in
//     * the <tt>indexes</tt> and <tt>sizes</tt>: two entries (index=a,size=b) and
//     * (index=a,size=b') are equivalent to a single entry (index=a,size=b+b').
//     *
//     * @param indexes current positions of the instructions to be resized. Each
//     * instruction must be designated by the index of its <i>last</i> byte, plus
//     * one (or, in other words, by the index of the <i>first</i> byte of the
//     * <i>next</i> instruction).
//     * @param sizes the number of bytes to be <i>added</i> to the above
//     * instructions. More precisely, for each i < <tt>len</tt>,
//     * <tt>sizes</tt>[i] bytes will be added at the end of the instruction
//     * designated by <tt>indexes</tt>[i] or, if <tt>sizes</tt>[i] is negative,
//     * the <i>last</i> |<tt>sizes[i]</tt>| bytes of the instruction will be
//     * removed (the instruction size <i>must not</i> become negative or null).
//     * @param begin index of the first byte of the source instruction.
//     * @param end index of the first byte of the target instruction.
//     * @return the future value of the given bytecode offset.
//     */
//    static int getNewOffset(
//            final int[] indexes,
//            final int[] sizes,
//            final int begin,
//            final int end) {
//        int offset = end - begin;
//        for (int i = 0; i < indexes.length; ++i) {
//            if (begin < indexes[i] && indexes[i] <= end) { // forward jump
//                offset += sizes[i];
//            } else if (end < indexes[i] && indexes[i] <= begin) { // backward jump
//                offset -= sizes[i];
//            }
//        }
//        return offset;
//    }
}
